The socialism with Chinese characteristics has entered a new era. The economic system in which multiple ownerships coexistence promotes the development of productivity on the one hand, and complicates the relationship between labor and capital on the other. In the era of the Industrial Revolution 4.0, the outbreak of artificial intelligencerelated technologies, ordinary workers face greater challenges, and labor relations tend to be tight. As the foundation of Marxist political economy, Das Kapital scientifically elaborates the relationship between capital and labor, and has important theoretical guiding significance for China to build a harmonious socialist relationship.